Automatic gas heater



June 3, 1941; w, A, AH M 2,243,953

AUTOMATIC GAS HEATER Filed April 15, 1959 a Sheets-Shet 1 W. A. GRAHAM June 3, 1941.

AUTOMATIC GAS HEATER Filed April 13, 1959' 4- 6 Sheets-Sheet 2 IllII!!!I!!!llifillllllrllllrlrlll keg Ql'lormeg June 3, 1941. w. A. GRAHAM AUTOMATIC GAS HEATER- F'il ed April 15, 1939 6 Sheets-Sheet 3 June 3, 1941. w, GRA AM 2,213,953

AUTOMATI C GAS HEATER Filed April 13, 1939 6 Shegts+$heet 4 o o o 9 I5 O O 0 O O O O C) rev i 68 If: I2 :25

22 I33 Ia Q I L lZl 4 138 $120 I WQ Jmuemkorc.

GHQ/meg June 3, 1941. w. A. GRAHAM AUTOMATIC GAS HEATER Filed Aprii 15, 1959 6 Sheets-Sheet 5 III/ll I/l/ III I I June 3, 1941. I w, GRAHAM AUTOMATIC GAS HEATER Filed April 13, 1939 GSheets-Sheet 6 Patented June 3, 1941 UNITED STATES PATENT OFFIQE AUTOMATIC GAS HEATER William A. Graham, Houston, Tex.

Application April 13, 1939, Serial No. 267,559

8 Claims.

My invention relates to heaters which are adapted to. employ gas as a fuel and which may be employed in connection with gas burners for toasting, heating and other similar purposes.

It is an object of my invention to provide a gas burner in which the gas which is fed to the burner also serves to operate a timing mechanism for the control of the burner.

Another object of the invention is to provide a timing mechanism for gas burners which may be automatically controlled through the flow of the gas therein. I

It is a further object of the invention to provide a controlling means for the delivery of gas to the burner which will be automatically adjustable in response to the temperature of the air adjacent the burner.

It is a further object of the invention to provide a pilot light to be used in connection with the burner which is controlled through the automatically operating mechanism and responsive to the flow of gas through the device.

This invention is an improvement upon my device disclosed in my prior patent, No. 2,105,858, issued January 18, 1938, and the invention resides particularly in the construction and assembly of the parts making up my improved apparatus and reference is made to the drawings herewith for a clear disclosure of the idea.

In the drawings herewith,

Fig. 1 is a side view partly in section showing the manner in which the device is housed for operation.

Fig. 2 is a central longitudinal section through the device illustrating the operating mechanism for control of the toast-carrying rack.

Fig. 3 is a similar longitudinal section taken from the opposite side of the device.

Fig. 4 is a tranverse section on the plane 4-4 of Fig. 3. I

Fig. 5 is a top plan view of the device with the housing removed.

Fig. 6 is a bottom plan view of the structure shown in Fig. 5. V

Fig. 7 is a side view similar to Fig. 2 but with the operating gear and the supporting plate therefor removed.

Fig. 8 is a broken detail illustrating the valve for the pilot light.

Fig. 9 is a top plan view of the gas motor employed with the invention.

Fig. 10 is a broken detail illustrating the control valve employed with the motor. Fig. 11 is a transverse section through the motor.

Fig. 12 is a similar section taken at right angles to the one shown in Fig. 11.

Fig. 13 is'a broken sectional detail illustrating the mounting of the cam disc. 1

While my invention is adapted for general use in connection with heaters I have illustrated the same as being employed upon a bread toasting device. This device includes an outer housing 5 of sheet metal which is of generally rectangular shape. The housing includes a base support 2 upon which the operating mechanism is 'supported. There is an upper cover plate 3 which is slotted longitudinally to allow ;the insertion of the toast into the same and to get a view of the operating mechanism. 1

With reference particularly to Figs. Sand 4, it will be seen that the lower supporting plateZ, which forms the floorof the heating chamber, has thereon two toasting chambers each having side plates 4, which are secured to the base plate 2 at their lower sides and are extended upwardly and bent inwardly at 5 to partially enclose a heating chamber 6. Each of the side plates is equipped with a plate I of heat insulating mate rial and I may have a second plate 3 between the side wall 4 and the housing I to further prevent the loss of heat outwardly from the chamber 6.

Centrally of each of the heating chambers 6 is a pair of guide frames 9 spaced apart to form between them a foraminated compartment ill in which the toast is to be placed. Said compartment It has therefore two spaced walls made up of rods or wires spaced apart so that the heat from the chamber 6 may find ready access to the sides of the bread to be'toasted. Each of the vertically extending rods 9 which make up the side walls of the compartment It is curved laterally at its upper end and hooked into a cross bar II which thus supports the rods at the upper end.

The heat is supplied to the chamber ii through burners l2. Said burners are made up of longitudinally extending pipes preferably rectangular in cross section, as shown in Fig. l, and with openings l3 spaced along the upper side to deliver the gas upwardly into the heating chamber.

With reference to Fig. 6, it will be seen that there are pipes I2 on opposite sides of each of the chambers 6. These two pipes are connected-by a cross ppie I4, which in turn has a forwardly extending member [5 connected with the gas pipe I6. The bottom wall 2 of the heating chamber is perforated, asshown at ll, to allow the passage of air to the burner through the lower portion of the chamber.

As will be seen from Fig. 6, the gas conducting pipes l6 have connection through the pipe It with both of the burners. Said pipe I6 extends upwardly through the floor plate 2 to receive gas from the pipe l9, which extends into the motor 9, as will be now described.

Referring to Figs. 9 to 16, inclusive, I have disclosed a motor which is in all respects practically the same as the motor disclosed in my prior Patent No. 2,105,858 above referred to. It is adapted to receive thereto, through an inlet pipe 20, a supply of gas coming from any source of gas under pressure, such as the usual household gas connections.

Said pipe delivers the gas into an upper chamber 2| formed in a housing 22 which is supported upon the upper end of the motor 23. The gas from the chamber 2| may pass downwardly to the two opposed gas chambers in the motor.

The motor includes an upper plate 24 with a central downwardly extending outlet passage 25 for the gas which gas is delivered through the pipe 19130 the burner. Theupper end of the passage 25 is covered by a valve plate 26. Said valve plate fits closely against an upper seat member 2? fitted into the plate 24. Through the plate 2'! are a series of openings 28', four in number, as will be seen from Fig. 10. The valve plate has a downwardly extending rim 29 fitting closely against the valve seat;

The' plate 25 has a'central opening at its upper side to-receive a pin 39 formed eccentrically on the lower side of a rotating shaft 3l and it will be seen that when the shaft 31 is rotated the disc will be moved in a path about the shaft so that one after another of the openings 29 will ,be exposed to receive the gas fromthe chamber 2!.

While one ofsaid openings is thus exposed to receiverthe gas'the opposite opening 32 will be connected with the exhaust opening 25 previouslyreferrod to. Connected with each of the openings 32 and 32' is a passage leading to one has apair of forked arms 36 on one side thereof;

said arms being connected with a lever 37, the opposite end of which is fixed to a shaft 38 journaled at eaohof itsends in the-walls of the housing. 'The upper end of the shaft projects through a stuifing box 89, into the upper housing 22 and has a laterally extending arm thereon which acts as a crank arm, the free end of which is connected by means of a link 3-! to a crank pin42 upon'the upper side of a disc ids'ecured on the shaft 3| previously referred to;

It will be seen that the two chambers on opposite sides of the motor housing are identical in' shafts '38 are bent in directions approximately atjright angles to each other, as will be seen from Fig. 9. Thus the movement of the diaphragms will move the arms Ml so asto give a rotating movement to the disc 53 and the shaft 3f in a counterclockwise direction, as'lshown in Fig. 9.

With the rotation of the shaft 3 l, the valve plate 26 will be moved so as to allow the passage of gas into the diaphragm chambers in the proper sequence to obtain the movement of the diaphragms and the shaft, as has been described.

The rotation of the shaft 3| will cause the movement of the pin $2 in a circle concentric with the shaft 3|. Said pin 42 is extended upwardly to engage within a disc 44, which is fixed to the lower end of a shaft 4-5 supported in a bracket 45 in thehousing 22. The upper end of the shaft i5 is journaled rotatably in a plug 4? screwed within the upper end of the housing.

Formed upon the shaft 35 is a worm gear 48 which is-operatively connected with a gear 49 upon a shaft 53, which is extended laterally through a stufiing box 5! in the housing 22 and has formed on its outer end a small gear 52.

It will be noted that the gas which is fed into the upper housing 22 through the pipe 28 may pass freely downwardly through the upper housing 22 to the motor and will be delivered by means of the operation of the valve 28 in sequence to the chambers of the motor, so as to cause the operation of the diaphragmsand the rotation of the shafts which omrate in turn the power shaft 31. In this way rotation may be communicated in the manner shown to the laterally extending gear 52. This motor, as will'be seen, operates in the same manner as does the motor of my prior patent.

Mounted within the heating chamber 8 is a toast-carrying rack 53. With reference to Fig. 5, it will be seen that the rack 53 has arms 54 extending longitudinally of the heating chambers 6 and movable simultaneously in a-vertical direction along the rods 9 previously described. Each of the arms 54'has laterally extending lugs 55 thereon which are formed: with openings to receive the rods '9 so that theracl; may be slidable vertically along said rods. Said frame 53 is connected its forward end to a frame member 55 which has a forwardly projecting handle 51.. There are upwardly and downwardly extending arms on the frame member 55 which are pivotally connected to an upper lever, arm 58 and to a lower lever arm 58. Said arms 58 and 59 are parallel and it will be seen therefore that the toast-carrying rack, including the supporting arms 54, will remainhorizontal during the movement of the levers 5B and 59.

The forward end of the lever 58 is pivoted at 60 upon a frame plate 6!. As will be seen particularly from Fig. 3, the forward end of the lever 58 is extended beyond the pivot and has a quadrant-shaped end. Thelower end of said quadrant-shaped head 52 has thereon a laterally extending post 3, which is adapted to engage with the latching mechanism which will be presently described.

The lower lever 59 is pivoted at 54 to the frame plate GI and has a downwardly extending arm 65, which isconnected at 66 to a link 61, which has a cross arm thereon engaging over the valve stem 58. The lower end of the arm is secured at 69 to a tension spring Til, which is connected at its other end to the base plate at ii.

The gear 52 upon the motor shaft engages with a large gear 12, which is mounted upon a shaft 13 supported in plates Hi in the housing. The shaft 13 has thereon a cam disc 75. Said disc hastwo laterally extending arms 53 and 94 thereon, which are adapted to'engage with the latching mechanism. Onone side of said disc i a laterally extending cam which has aninclined surface I9 thereon, which engages with a similar inclined cam surface 80 formed upon a downwardly depending arm 8| pivotally connected at 82 to a valve housing 83.

The valve housing 83 encloses the pilot light operating valve shown in Fig. 8. It will be seen that the housing 83 in that figure has an inlet pipe 84 and an outlet pipe 85. The interior of the valve chamber 66 in the housing has a passage from the inlet to the outlet pipe controlled by a valve 81, said valve fitting within a seat in the passage between the two pipes and has a stem 88 extending through the forward wall of the chamber and secured at its outer end to a head 89. A spring fitting about the valve stem tends to hold the head 89 outwardly to close the valve in the passage. When the arm 8| is moved against the head 89 it will move the valve 8'! to open position, allowing the passage of gas from the pipe to the pipe 65.

The movement of the shaft I3 will carry the cam disc I5 around in a clockwise direction. The driving connection between the cam disc and the shaft I3 is shown in Fig. 13. The shaft 13 extends through the wall or plate I4 and has secured thereto adjacent the wall a friction disc 90, said disc being held rotatable with the shaft. The cam disc I5 is held in frictional engagement with the disc 90 by means of a spring 9| on the shaft bearing at one end against the head 92 of the shaft and at the other against the cam disc. Thus the said cam disc is held normally in frictional engagement with the friction disc 90 and will rotate therewith. The cam disc may, therefore, be rotatable independently of the shaft I3 and disc 90 by a slipping of one relative to the other.

As will be seen in Fig. 7, the cam disc I5 has a laterally extending arm 93 adjacent one edge thereof and an opposite arm 94 somewhat longer than the arm 93, which as will be later noted, is adapted to be engaged by an arm of the frame to move the cam disc.

When the frame is moved to its lowest position to bring the toast-carrying rack adjacent the burner, the laterally extending pin 63 thereon is engaged within a notch 95, formed in the upper side of the latching member 96. Said latch is pivoted at one end upon a pin 97 secured withinthe frame 6|. Said latch is extended upwardly in an inclined direction and as a cam surface 99 adjacent the notch 95, which tends to depress the latch as the pin 63 on the frame is swung upwardly into latching position. The upper end of the latch 96 has a finger 99 thereon toward the extremity of which is a pin I connected to a spring IOI secured at its upper end to a pin I92, so as to exert a pull upwardly upon the latch.

There is a hand lever I03 which is extended from the upper end of the housing downwardly for connection at its lower end to an arm I94, which is in turn directed downwardly and pivoted upon the pin 91 previously described. On the arm I94 is a forwardly projecting finger I65, which has a cam surface I06 engaging against a wedge-shaped block I0'I. Said block rests upon the upper end of the latching lever and it will be understood that when the arm I is depressed it will move the wedge block I91 and the latch lever downwardly to disengage the latch from the pin'63 upon the lever 58.

The wedge block I6! is pivotally connectedto a link I08. which is in turn connected to a pivot in dotted'lines in that figure.

pin I09 at the outer end of a crank arm IIO. Said crank arm is fixed upon a shaft III, which projects through the plate to the opposite side thereof. 5

With reference to Fig. 3, it will be seen that I have a post II2 mounted upon the base plate 2 and extending upwardly at the forward side of the housing. There is formed thereon an inwardly extending arm I I3 which projects into the heating chamber at a point between the two burners. At its forward end is a block II4 upon the upper surface of which is secured aplate I I 5 of a thermostat. This metal is adapted to be moved upwardly at its forward end II6 when subjected to heat. This is a common type of thermostat now in general use. The upward movement of the member H5 will communicate the interior chamber of the toaster which is adjustable to suit the conditions of each particular installation. Referring back to Fig. 7, it will be noted that the side of the arm I03 presented inwardly is formed with a cam surface II9 shown Thus when the cam disc is rotated in a clockwise direction the pin 93 will contact with the cam surface H9 and depress the arm I04 so as to move the cam block I01 downwardly to unlatch the latch member and release the toast-carrying rack. The rota tion of the cam at a uniform predetermined speed due to the operation of the motor, will bring the pin I6 into contact with the cam surface II9 after a predetermined interval. This interval may be shortened, however, when the heating chamber heats up to such an extent as to effect the thermostat and thus cause a rota tion of the shaft III. Said rotation will be in a clockwise direction, as shown in Fig. 7, and will exert a pull upon the link I08 to move the wedge block I01 to the right,'thus bringing the wider portion of the wedge block beneath the arm I05. In this manner the arm I05 will be moved upwardly as the wedge block moves to the right and the cam surface II9 will be more quickly engaged by the pin I6 to release the latch. By this means the latch will operate after a somewhat shorter interval where the heating chamber is heated up than it will where the'heating chamber has beenv motor and to the burner will now be described.

With reference to Figs. 3 and 6, it will be seen that the gas coming to the device will pass through the pipe I20 into a valve chamber -I2I. Said valve chamber is formed with a tapered seat I22 to receive a tapered valve member I23. Said valve closes the passage of gas from the chamber I2I to the chamber I24. It has a stem I25 projecting through a stuffing box into engagement with a head I 26 having thereon the outwardly extending stem 68 previously" referredtm The-chamber l'2l. is-connected with the pipe I21 which, as seen in Fig. 5, passes into the upper chamber through the port 20' previously noted. The'gas then passes through the motor and; outwardly throughthe pipe l9 to connect with the pipe l6. leading to the burners: It is therefore to be noted that the. gaswhioh serves-to operate the motor exhausts through the. pipe l6 and 18.

to feed the burners. below the heating. chambers.

It will be understood that the release of the toast-carrying racl; will be accomplished automatically .under usual operating conditions but that the release of the. latch maybeaccomplished by the movement of the lever arm. Hi3. .The'device is entirely enclosed'within. the outer housing 3 and to engage the. lever [03 a push rod. 12.8 is mounted longitudinally: of thehousing and upon theupper plate 3. Said pushrod hasat its inner end a contacting arm I29,;which isslidableupon a plate I38 and is in position to. engageiwith the lever arm {03' and push it to the left. to release the toast-carrying rack.

A spring 13 is provided. to withdrawthe push rod when the arm N93 has been'moved. 'This push rod has a :handle I32 atv the. forwardside of the housing for the operation of the rod.

The operation of the. device'has been already described. It will be understood that when the toast is to betoasted it is placed vuporrthe toastcarrying arms Sdthroughslots; in the upperend of the housing and the handle is. depressed to move therack intoposition adjacent the burn.- ers and to carry the. pin 63 on: the upper lever arm intoengagement with the latch 9.5 as was previously described. This will; hold the rack in its lower position. until'releasedp The movement of. the. two lever arms 58: as the rack. is

depressed will alsdmove the arm 65 upon the lower lever arm 59 to openthe. passage of gas to the motor. viously described to rotate the small gear 52. and theilarger gear l2 connected therewith-so as to rotate the operating. shaft 13. from the motor to. the burners and-the gas at the burners will be ignitedfrom the. pilotlight. The pilot light is fed with .gas from the main lineifiil, as seeninFig. 6..: A branch pipe I33 leads oii. from the chamber 124 and has therein avalve member I34 which may be employed to regulate the .rate of supply of gasthroughthe pipe I33. Said pipev [33" passes upwardlythrough the bottom of the housing, as shown in Fig. 5,

and. enters the valve chamber '83 through the inlet 8 When the. valve 81 in said valve cham-' her is opened it will passv outwardly through the pipe 35 and will pass bachdownwardlyv through the base. plateand issue at I35, as shown in- Fig. 6, andwill thencebe conducted to the pilot.

' adjacent the burner 53.

It will be noted that when the toastrack is moved downwardlyit will move the cam disc l5 into a position with the cam F8 thereon bean ing against the cam surface upon the'lever arm 8!, thus tending to depress.the'headtarupon the gas tothe pilot light. 1 It will bexunderstood that the gasiva'lves i 22 .and the valve 81 -in;-the pilOt;

light control valve will beseated loosely so'as The gas will pass The motorwi-ll operate as. premove the wedge block I91.

apes-e53 to'allow the passage of some gasto; the pilot light at. all times but. that when the valve 81- is depressed by the arm 8|. asdescribed a suflicient amount of gas will be ied to the. pilot .light to cause a strong upward flame while the cam 18 is in contact with the arm. 7

After the rack has been lowered and latched as described the gas valve will be openeddue to the movement of the arm 65 on the rack to raise said arm in engagement. with the end of the valve stem ES to open-the valve and feed the gas to the burners as described. This :gas passing by way of the motor will cause the-rotation of the cam 15 in a clockwise direction-so as to move the pin 93 thereon into position to release the latch after a predetermined time ordinarily sufiicient to toast the bread u-pon'the rack. This period maybe shortened as previously described by the thermostat acting to When the latch 96 has been depressed sufficiently through the. engagement of the pin 93- with the arm-- I64 the rack, will be free to be thrown upwardly into its original position through'the action of: the

spring it.

When the arm 58 is thus moved upwardly en gagement is had between an arm MBand the pin 9 uponthe cam disc; Saidarm M0- isconnectedadjustably with the forward ..end of the leverl t, as will be seen in Fig. 3.. The arm has a downwardly projecting portion which is slotted to receive a set screw ill, through which it may be adjusted toward: and away from the pin--94; There is a branch; I52. on the arm l ldwhic'h projects laterally within the. path' of. the-pint! slipping the cam disc onthe frictiondisc 90 control valve 81 and thus permit the passage of r adjacent thereto. Itwill be'understood that due to themeshing ot the gears 52 and 12 theshaft 73 will not be rotatablein a counter-clockwise direction but theedisc l5 may be iriotionally moved relative towtheshaft so asto allow the cam disc 15 to be rotated back to itsoriginal position so that the operations may be again re sumed in'the order described.

My presentinventionhas certain advantages over the structure shown in my prior patent above referred to-in that the controlof'the gas to the motor and to the burner is more: positive andreliable. Furthermore, the control of the period. during which the toast issubjectedtothe heat is more satisfactory in that it. perates in response to the. temperature within the he'ating'chamber or oven. .As the said temperature'is raised the period that the toast is exposed Within the ovenis decreasedsofthat in all cases the toast will be discharged at the proper time-without burning. The further advantages of this construction will be apparent to those skilled in the art. p'

What is'cla-im ed is: i

1'. 'A gas burner, a food carryingrack; means to move said rack towardv said burner; means to" automatically latohsaid rack -in-position adjacent said burner, a spring tending" to move" When the- EJ711153 is. releasedhy said frame away from said burner, a gas conducting line leading to said burner, a normally closed valve in said line, means operated by said rack moving means to open said valve, a motor operated at a uniform speed by the flow of gas to said burner, means operated by said motor to release said rack after a predetermined interval, and means responsive to the heat adjacent said burner to adjust said last means to shorten said interval as said burner heats up.

2. A gas burner, a food carrying rack, means to move said rack toward said burner, means to automatically latch said rack in position adjacent said burner, a spring tending to move said frame away from said burner, a gas conducting line leading to said burner, a normally closed valve in said line, means operated by said rack moving means to open said valve, a motor operated at a uniform speed by the flow of gas to said burner, means operated by said motor to release said rack after a predetermined interval, a thermostat adjacent said burner, a shaft operatively connected for rotation by said thermostat in response to heat adjacent said burner, and means operated from said shaft to adjust said last means to shorten said time interval.

3. A gas burner, a food carrying rack, means to move said rack toward said burner, means to automatically latch said rack in position adjacent said burner, a spring tending to move said frame away from said burner, a gas conducting line leading to said burner, a normally closed valve in said line, means operated by said rack moving means to open said valve and deliver a uniform flow of gas through said line, a motor connected in saidline and operated at a constant speed by said gas, a gear operated from said motor, a cam disc operated from said gear, a lever pivoted adjacent said latch and movable to release said latch, means on said cam disc to move 1 said lever after a predetermined period of operation, a wedge block between said last named means and said lever and means responsive to the rise of temperature at said burner to move said wedge block to shorten the interval before the release of said latch.

4. In a device of the character described, a gas burner, a gas line leading to said burner, a normally closed valve in said line, a gas operated motor in said line between said valve and said burner, a food carrying rack, a lever supporting said rack and pivoted to swing said rack to and from said burner, a latch positioned to automatically engage and latch said lever in position with said rack adjacent said burner, means on said lever to open said valve, a shaft rotatable at a uniform speed by said motor, a cam disc thereon, a releasing lever pivoted adjacent said latch, an arm on said lever, a wedge block between said arm and said latch, a pin on said cam disc positioned to engage said lever after a predetermined period of rotation, a thermostat adjacent said burner, and means operable by said thermostat to move said wedge block to shorten the interval before said latch is released.

5. In a device of the character described, a gas burner, a gas line leading to said burner, a normally closed valve in said line, a gas operated motor in said line between said valve and said burner, a food carrying rack, a lever supporting said rack and pivoted to swing said rack to and from said burner, a latch positioned to automatically engage and latch said lever in position with said rack adjacent said burner, means on said lever to open said valve, a shaft rotatable at a uniform speed by said motor, a cam disc thereon, a releasing lever pivoted adjacent said latch, an arm on said lever, a wedge block between said arm and said latch, a pin on said cam disc positioned to engage said lever after a predetermined period of rotation, a thermostat adjacent said burner, a shaft rotatable by said thermostat in response to the heating up of said burner, a crank arm thereon, and a link on said crank arm connected with said wedge block to move said block and shorten the interval before which said latch is released.

6. .A gas burner, a food carrying rack, means to move said rack toward said burner, means to automatically latch said rack in position adjacent said burner, a spring tending to move said frame away from said burner, a gas conducting line leading to said burner, a normally closed valve in said line, means operated by said rack moving means to open said valve, a gas operated motor between said valve and said burner, a pilot light adjacent said burner, a pipe connected with said gas line and connected with said pilot light, a control valve in said pipe, a cam disc operated by said motor, means on said disc to cause the release of said latch after a predetermined period, and additional means on said disc to open said control valve and increase the passage of gas to said pilot light.

'7. A heating chamber, a main gas burner therein, a pair of parallel levers pivoted adjacent said chamber, a food carrying rack mounted on said levers and movable toward said burner, a spring tending to move said rack to position away from said burner, a gas line leading to said burner, a motor in said line, a latch for said levers to retain said frame in lowered position, a pilot light burner adjacent said main gas burner, a branch line leading thereto, a pilot light valve in said branch line, a cam disc rotatable from said motor at a uniform speed, means responsive to the rotation of said disc to release said latch after a predetermined interval, a lever arm movable by said disc to open said pilot light valve, and means on said disc operable when said rack is moved to a position adjacent said burner to rotate said disc to cause said disc to move said lever arm.

8. In a gas fired toaster, a food rack, a latch to hold said rack in position to toast the food therein, adjustable means operated by the gas fuel to release said latch, and additional means responsive to the heat adjacent the rack to adjust said first means to vary the interval before release in proportion to such heat.

WILLIAM A. GRAHAM. 

